Abstract: The present invention relates to a process for the preparation of multimodal ethylene homo- or copolymers in at least two stages, the process comprising preparation of a first ethylene homo- or copolymer fraction in a loop reactor in slurry phase, preparation of a second ethylene homo- or copolymer fraction in a gas phase reactor, by using a catalyst not containing an inorganic oxide support, and operating the gas phase reactor in such conditions that at least part of the gas is recycled, and that at least a part of the recycled gas is condensed and the (partially) condensed gas is re-introduced into the gas phase reactor.
Type:
Grant
Filed:
August 8, 2006
Date of Patent:
December 14, 2010
Assignee:
Borealis Technology Oy
Inventors:
Henrik Andtsjoe, Michiel Bergstra, Ralf Karlsson, Klaus Nyfors, Urban Thorngren